Liquid crystal display with switchable viewing angle and method of viewing angle control

Abstract

An LCD includes a first substrate, a second substrate, and a liquid crystal layer. The first substrate is provided with a first electrode. The first electrode is provided with a plurality of first elongated electrodes. The second substrate is provided with a second electrode and a third electrode. The second electrode is a common electrode and the third electrode is a pixel electrode. The second electrode is provided with a plurality of second elongated electrodes. The first elongated electrodes and the second elongated electrodes are arranged alternately, and the first elongated electrodes have no overlap with the second elongated electrodes. When no bias voltage is applied between the first electrode and the second electrode, the LCD is displayed with a wide viewing angle; and when a bias voltage is applied between the first electrode and the second electrode, the LCD is displayed with a narrow viewing angle.

What is claimed is: 
     
       1. An LCD (liquid crystal display) with switchable viewing angle, comprising:
 a first substrate being provided with a first electrode, wherein the first electrode is provided with a plurality of first elongated electrodes; 
 a second substrate being provided with a second electrode and a third electrode, wherein the second electrode is a common electrode for inputting a common voltage to the LCD, the third electrode is a pixel electrode formed in the sub-pixel areas of the LCD, the second electrode is provided with a plurality of second elongated electrodes, the first elongated electrodes and the second elongated electrodes are arranged alternately, and the first elongated electrodes have no overlap with the second elongated electrodes; and 
 a liquid crystal layer being sealed between the first substrate and the second substrate, wherein the liquid crystal layer is provided with a plurality of negative liquid crystal molecules; 
 wherein when no bias voltage is applied between the first electrode and the second electrode, the LCD is displayed with a wide viewing angle; and when a bias voltage is applied between the first electrode and the second electrode to generate an inclined electric field between the first elongated electrodes and the second elongated electrodes, the LCD is displayed with a narrow viewing angle. 
 
     
     
       2. The LCD of  claim 1 , wherein the LCD further comprises a plurality of scanning lines and a plurality of data lines, the sub-pixels areas are defined by the scanning lines and the data lines intersecting with each other, a sub-pixel is formed in each sub-pixel area, and the sub-pixels are arranged in rows and columns. 
     
     
       3. The LCD of  claim 2 , wherein the second elongated electrodes are formed at a central portion of each sub-pixel area, and the first elongated electrodes are formed at two opposite sides of each second elongated electrode. 
     
     
       4. The LCD of  claim 2 , wherein the first electrode is further provided with a first connecting line, and the first elongated electrodes extend perpendicularly from the first connecting line. 
     
     
       5. The LCD of  claim 4 , wherein the second electrode is further provided with a second connecting line, and the second elongated electrodes extend perpendicularly from the second connecting line. 
     
     
       6. The LCD of  claim 5 , wherein each sub-pixel has a length direction along the data lines, the first connecting line and the second connecting line extend along the direction of the scanning lines, the first connecting line and the second connecting line are located respectively at lower and upper sides of each row of sub-pixels. 
     
     
       7. The LCD of  claim 6 , wherein the first elongated electrodes and the second elongated electrodes extend along the direction of the data lines. 
     
     
       8. The LCD of  claim 5 , wherein each sub-pixel has a length direction along the scanning lines, the first connecting line and the second connecting line extend along the direction of the data lines, the first connecting line and the second connecting line are located respectively at left and right sides of each column of sub-pixels. 
     
     
       9. The LCD of  claim 8 , wherein the first elongated electrodes and the second elongated electrodes extend along the direction of the scanning lines. 
     
     
       10. The LCD of  claim 2 , wherein a first elongated gap is formed between every two neighboring first elongated electrodes, and the second elongated electrodes are disposed corresponding to the first elongated gaps. 
     
     
       11. The LCD of  claim 10 , wherein a second elongated gap is formed between every two neighboring second elongated electrodes, and the first elongated electrodes are disposed corresponding to the second elongated gaps. 
     
     
       12. The LCD of  claim 2 , wherein the third electrode in each sub-pixel area includes a plurality of third elongated electrodes. 
     
     
       13. The LCD of  claim 12 , wherein a portion of the third elongated electrodes are overlapped with the second elongated electrode, another portion of the third elongated electrodes are overlapped with the first elongated electrodes. 
     
     
       14. The LCD of  claim 2 , wherein the first substrate is a color filter substrate, the second substrate is a thin film transistor array substrate. 
     
     
       15. An electronic device, comprising:
 the LCD of  claim 1 ; and 
 a driver IC electrically connected with the LCD for driving the LCD. 
 
     
     
       16. The electronic device of  claim 15 , wherein the electronic device is provided with a control button for controlling the viewing angle of the LCD. 
     
     
       17. A method of controlling the viewing angle of the LCD of  claim 1 , comprising the steps:
 when the LCD is required to display with a wide viewing angle, applying no bias voltage between the first electrode and the second electrode; 
 when the LCD is required to display with a narrow viewing angle, applying a bias voltage between the first electrode and the second electrode. 
 
     
     
       18. The method of  claim 17 , wherein the bias voltage applied between the first electrode and the second electrode is in the range of 4V to 7V.